Chapter SeventeenEnvironmental HealthEnvironmental Health Encompasses all the interactions of humans with their environment and the health consequences of these interactions.Environmental Health Concerns The field of environmental health grew from the efforts to control communicable diseases Pathogens were recognized when seen living and being transmitted via drinking water, sewage, and food These successful efforts to control and prevent communicable diseases changed how we currently treat water and waste productsClassic Environmental Health Concerns Communicable Diseases Clean Water Waste Products Food Insect and Rodent ControlCommunicable Diseases Insects and rodents carry microorganisms (animal hosts) =vectors Systematic garbage collection, sewage treatment, water protection, food inspection an public health agencies These issues still are a major issue in the world. Natural disasterClean Water Physical and chemical process Screening and chlorine Fluoride 1 million US citizens become ill from contaminated water Water shortage is also a concernSewage Humans generate large amounts of waste such as sewage  Sewage Plants separate fecal matter from water, treat it so it can not transmit disease, and release the water. Sludge can be used as fertilizer as long as it does not contain heavy metalsWaste Disposal Solid waste is buried in sanitary landfill disposal sites Largest component of household trash is paper followed by yard waste and metals Despite precautions, buried contaminants do leak into surrounding soil and groundwater Many communities encourage recyclingInsect and Rodent Control Mosquitoes - encephalitis Ticks - Lyme disease Fleas - Bubonic Plague, hantavirus, tapeworms, and Salmonella The use of pesticides, protective clothing, and basic caution will protect against spreadFood Inspection Diseases and death are associated with food-borne illnesses and are on the decline The United States Department of Agriculture (USDA) is responsible for overseeing and regulating certain food items - meats and grains Overall, the food distribution system in the United States is safe and efficient However, it is estimated that every American suffers from 2-3 episodes of food-borne illness every yearPopulation Growth The world’s population is currently about 6.5 billion and is increasing at a rate of about 78 million per year The United Nations projects that the world population will increase to 9.1 billion by year 2050 This rapid expansion of population is generally believed to be responsible for most of the stress humans put on the environmentFactors Which Limit Population Growth Food - maybe a shift to vegetarian diets because animals require so many resources Available land and water - forests, depletes soil, withdraws water Energy - shift to renewable resources such as hydropower, solar, wind Minimum acceptable standard of living The earth can not sustain the US energy consumption on a worldwide basisFactors That Contribute to Population Growth High fertility rates Lack of family planning resources Lower death ratesEffects due to Air Pollution The Greenhouse Effect and Global Warming CO2 and other natural gases act as a blanket to keep the sun’s heat close to the surface of the earth Experts predict a 2.5 - 10.4 degree temp rise by 2100 Thinning of the Ozone Layer Protects earth from Ultraviolet rays of sun Destroyed by Chlorofluorocarbons from refrigerants, aerosol sprays and solvents CFC’s are banned but stay in atmosphere for hundred years Acid Precipitation - a combination of atmospheric pollution and moisture Ex. Burning of coal - gases are carrying for long distancesEffects due to Air Pollution Energy consumption is the root of problem 85% of energy used comes from fossil fuels Car exhaust, industrial oil burning, and coal burningForms of Indoor Pollution Environmental tobacco smoke (ETS) Carbon monoxide and other combustion by-products Formaldehyde gas Biological pollutantsTypes of Chemical Pollutants Asbestos - used in insulation and as fire retardant Lead - cause central nervous system damage Pesticides - overuse and abuse Mercury - affects central nervous system Slows fetal development, brain damageOther Forms of Pollutants Radiation - comes in different forms Gamma rays - produced by nuclear weapons, nuclear energy plants, and radon gasare biggest concern Home radiation affects are inconclusive Radon - found in soil, rocks, and building materials increase the risk of lung cancer but long term affects unknown Noise Pollution - exposure over 80 -85 decibels can be permanent Concert, workplace loss occurs the first 2 hours and returns in 2 hours Tinnitus - constant ringingHow Can You Heal the Environment? Share what you learn about environmental issues with your friends and family Join, support, or volunteer your time to organize environmental causes that are important to you Contact your elected officials to communicate your concernsSteps to prevention Cut back on driving - carpool Tune-ups Energy efficient appliances Fluorescent light bulbs Fans instead of AC Plant trees Ventilate your home and keep houseplants  Clean